Heat lamp vs incandescent

I read in another thread about a chameleon gaping under its heat lamp and to raise the lamp or lower the wattage; I also read that incandescents can be used to provide heat. My question is this: how do wattages compare? My guy had been gaping under his light and lowering his branch only made him climb the screen (which is what was said would happen in the other thread) So I really can't raise the light up any higher so the lower wattage would be what I need to do. My heat lamp is 75 watts so are incandescents comparable? Would the next step down be a 60 watt incandescent?

Incandescent bulbs are cheap. Go buy one of each between 40 and 75 watts and adjust throughout the year as needed to keep basking temps to the recommended for your species.

I didn't notice you mention a temperature. It is vital to monitor the temps in the basking area. You should know what they are throughout the day and they will change throughout the year.

They range from 80-85 if the ambient temp is less than that in the room. I do have AC so it is rare that the room would be warmer than that. Even so I thought they needed a "concentrated" area to bask. During the day the ambient temp in the cage is 70-75 and at night the cage is about 60-65. I live in a big drafty old house so sometimes in the winter I leave a heat source on just in case.

There should be a range in the enclosure. The basking area, the branch under the light emitting heat, should be warmer than the bottom / middle of the enclosure. You probably don't want the entire enclosure to be 80 - 85, just the basking spot.

I was recommended the PAR20 halogen 50 watt flood bulbs and now use them and my Cham loves it. You can find them at Home Depot for like 5 dollars. 9 inches from an angle I get about 87 degrees. The light is very natural and 50 watt puts out the perfect amount of heat on that bulb

Just think of incadescent bulbs as heat emitters, the higher the wattage the more heat the lamp will create when lit.